• Imaging Science in Dentistry
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• 제44권2호
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• pp.121-128
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• 2014

Purpose: The present study was performed to compare the planning of implant placement based on panoramic radiography (PAN) and cone-beam computed tomography (CBCT) images, and to study the impact of the image dataset on the treatment planning. Materials and Methods: One hundred five partially edentulous patients (77 males, 28 females, mean age: 46 years, range: 26-67 years) seeking oral implant rehabilitation were referred for presurgical imaging. Imaging consisted of PAN and CBCT imaging. Four observers planned implant treatment based on the two-dimensional (2D) image data-sets and at least one month later on the three-dimensional (3D) image dataset. Apart from presurgical diagnostic and dimensional measurement tasks, the observers needed to indicate the surgical confidence levels and assess the image quality in relation to the presurgical needs. Results: All observers confirmed that both imaging modalities (PAN and CBCT) gave similar values when planning implant diameter. Also, the results showed no differences between both imaging modalities for the length of implants with an anterior location. However, significant differences were found in the length of implants with a posterior location. For implant dimensions, longer lengths of the implants were planned with PAN, as confirmed by two observers. CBCT provided images with improved scores for subjective image quality and surgical confidence levels. Conclusion: Within the limitations of this study, there was a trend toward PAN-based preoperative planning of implant placement leading towards the use of longer implants within the posterior jaw bone.

• Archives of Plastic Surgery
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• 제46권3호
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• pp.248-254
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• 2019

Background No head to head comparison is available between surgical lip lifting and upper lip filler injections to decide which technique yields the best results in patients. Despite the growing popularity of upper lip augmentation, its effect on societal perceptions of attractiveness, successfulness and overall health in woman is unknown. Methods Blinded casual observers viewed three versions of independent images of 15 unique patient lower faces for a total of 45 images. Observers rated the attractiveness, perceived success, and perceived overall health for each patient image. Facial perception questions were answered on a visual analog scale from 0 to 100, where higher scores corresponded to more positive responses. Results Two hundred and seventeen random observers with an average age of 47 years (standard deviation, 15.9) rated the images. The majority of observers were females (n=183, 84%) of white race (n=174, 80%) and had at least some college education (n=202, 93%). The marginal mean score for perceived attractiveness from the natural condition was 1.5 points (95% confidence interval [CI], 0.9-2.18) higher than perceived attractiveness from the simulated upper lip filler injection condition, and 2.6 points higher (95% CI, 1.95-3.24) than the simulated upper lip lift condition. There was a moderate to strong correlation between the scores of the same observer. Conclusions Simulated upper lip augmentation is amenable to social perception analysis. Scores of the same observer for attractiveness, successfulness, and overall health are strongly correlated. Overall, the natural condition had the highest scores in all categories, followed by simulated upper lip filler, and lastly simulated upper lip lift.

• Journal of Mechanical Science and Technology
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• 제17권10호
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• pp.1443-1449
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• 2003

Primary goal of adaptive observers would be to estimate the true states of a plant. Identification of unknown parameters is of secondary interest and is achieved frequently with the persistent excitation condition of some regressors. Nevertheless, two problems are linked to each other in the classical approaches to adaptive observers; as a result, we get a good state estimate once after a good parameter estimate is obtained. This paper focuses on the state estimation without parameter identification so that the state is estimated regardless of persistent excitation. In this direction of research, Besancon (2000) recently summarized that most of adaptive observers in the literature share one common canonical form, in which unknown parameters do not affect the unmeasured states. We enlarge the class of linear systems from the canonical form of (Besancon, 2000) by proposing an adaptive observer (with additional dynamics) that allows unknown parameters to affect those unmeasured states. A recursive algorithm is presented to design the proposed dynamic observer systematically. An example confirms the design procedure with a simulation result.

• 대한디지털의료영상학회논문지
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• 제11권2호
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• pp.63-68
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• 2009

Among various physical or subjective assessments of the quality of X-ray images, physical assessments can be quantitative but they are eventually judged by the view of observers thus subjective assessments including the aspect of observers are required. The changes in the ability to detect lesions caused by changes in the thickness of acrylic plates were tested with the ROC interpretation method that has taken into consideration, all the features of physical assessments as well as observers' ability to observe and mental stages and even surrounding environments using an Alvim phantom and the result indicated that as the thickness of acrylic plates increased, the amount of noises occurred increased compared to signals and thus the ability to detect signals as well as the sensitivity that is an ability to signals accurately and the ability to distinguish noises from signals thus it is considered that more efforts of radiologic technologists will be required to detect small lesions of fat patients with diagnostic X-ray generating apparatus.

• Journal of Power Electronics
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• 제16권3호
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• pp.1131-1140
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• 2016

A simple design for a sliding mode observer is proposed for EV lithium battery SOC estimation in this paper. The proposed observer does not have the limiting conditions of existing observers. Compared to the design of previous sliding mode observers, the new observer does not require a solving matrix equation and it does not need many observers for all of the state components. As a result, it is simple in terms of calculations and convenient for engineering applications. The new observer is suitable for both time-variant and time-invariant models of battery SOC estimation, and the robustness of the new observer is proved by Liapunov stability theorem. Battery tests are performed with simulated FUDS cycles. The proposed observer is used for the SOC estimation on both unchanging parameter and changing parameter models. The estimation results show that the new observer is robust and that the estimation precision can be improved base on a more accurate battery model.

• Journal of Power Electronics
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• 제14권5호
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• pp.967-979
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• 2014

This paper focuses on speed and current sensor fault detection and isolation (FDI) for induction motor (IM) drives. A new, accurate and high-efficiency FDI approach is proposed so that a system can continue operating with good performance even in the presence of speed sensor faults, current sensor faults or both. The proposed three paralleled adaptive observers are capable of current sensor fault detection and localization. By using observers, the rotor flux and rotor speed can be estimated which allows the system to run under the speed sensorless vector control mode when a speed sensor fault occurs. In order to detect speed sensor faults, a threshold-based scheme is proposed. To verify the feasibility and effectiveness of the proposed FDI strategy, experiments are carried out under different conditions based on a dSPACE DS1104 induction motor drive platform.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권3호
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• pp.91-97
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• 2006

A major difficulty with the practical application of the multiple observer based IFDI schemes is the computational burden of the residual generation. In this paper, a new residual generator that employs function observers is proposed to reduce the computational burden, and the design methods of the IFDIS, equipped with the residual generator, are presented. The function observers employed in the residual generator can be considered as a dual of the unknown input (function) observer And it can be designed to estimate the measurement errors that are due to sensor faults. The error estimates are further processed to generate the residuals by which reliable fault detection/isolation result car be obtained. The proposed scheme is more useful, in real-time application, than any other multiple state observer based IFDISs. It can be effectively applied to fault tolerant control because the failure effects can be compensated by the use of the estimates of measurement errors. The proposed IFDI scheme is applied to an inverted pendulum control system for the IFDI of failed sensor and fault compensation.

• 한국측량학회지
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• 제18권2호
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• pp.157-168
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• 2000

평지보다 가용 면적이 많은 산지의 개발은 협소한 도시적 용도의 토지의 부족으로부터 기인한 많은 도시문제를 해결하기 위한 해결책으로 등장하고 있다. 산지를 개발할 경우에는 자연경관을 고려한 개발이 되어야만 하며 경관을 고려한 산지개발을 효과적으로 수행하기 위해서는 관찰자들이 어떠한 경관요소에 의해서 경관을 평가하는가를 객관적으로 파악하는 연구가 선행되어야 한다. 본 연구는 경관을 고려한 산지개발의 기초적인 연구로서 경관선호도 요인 분석에 있어서 GSIS와 ANN을 이용하였다. 연구결과 관찰자들은 여러 가지 경관요소 중에서 주로 산정의 표고와 건물의 표고와의 차이인“높이차”에 가장 많은 영향을 받는 것으로 나타났으며 그 다음으로는 용적률, 건폐률 순으로 경관평가에 영향을 받는 것으로 나타났다.

• 한국안전학회지
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• 제38권4호
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• pp.23-31
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• 2023

Revising the Occupational Safety and Health Act led to enacting and revising related laws and systems, such as placing fire observers in hot workplaces. However, the operating standards in such cases are still ambiguous. Although fire accidents occur through multiple and multi-step factors, the hazards of fire accidents have been identified in this study as individual rather than interrelated factors. The aim has been to identify multiple factors of accidents, outlining fire and explosion accidents that recently occurred in the domestic manufacturing industry. First, major keywords were extracted through text mining. Then representative accident types were derived by combining the main keywords through the co-word network analysis to identify the hazards and their relationships. The representative fire accidents were identified as six types, and their major hazards were then addressed for improving safety measures using the identification of hazards in the "Risk Assessment" tool. It is found that various safety measures, such as professional fire observers' training and clear placement standards, are needed. This study will provide useful basic data for revising practical laws and guidelines for fire accident prevention, system supplementation, safety policy establishment, and future related research.

• 산경연구논집
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• 제15권2호
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• pp.11-18
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• 2024

Purpose: This research examines how people react to nonconforming behavior such as entering a luxury boutique wearing gym clothes rather than an elegant outfit or wearing red sneakers in a professional setting. Nonconforming behaviors, as costly and visible signals, can act as a particular form of conspicuous consumption and lead to a positive inference of status and competence in the eyes of others. Research design, data, and methodology: A series of studies demonstrate that people confer higher status and competence rather than conforming individuals using 2-way ANOVA through employees in luxury stores and students at university. Results: According to the empirical studies, observers who witness the nonconformity behavior have positive inferences of status and competence rather than conformity behavior. These positive inferences derived from signals of nonconformity are moderated by individual differences in prior knowledge and regulatory focus. Conclusions: Through three empirical studies, observers who witnessed role-breaking in prestigious and professional situations found that the individuals who performed the nonconformity behavior had higher status and competence rather than conformity behavior. Even in Korea, a collectivist culture, observers who witnessed nonconformity behavior showed that they gave higher evaluations to the people who behaved informally.